The shape of a device such as an electronic device is analyzed after or during design using radio wave that the device transmits. In performing the radio wave analysis, the shape of the device is taken in radio wave analysis software as an object model in which a polygon mesh (hereinafter, referred to merely as “mesh”) is set as a basic unit and thereby design of the shape of the device is made on a virtual space formed within a computer.
In the computer's virtual space, a sketch plane is used as a reference plane. FIG. 13 illustrates an example of a sketch plane and an object model. More specifically, FIG. 13 illustrates a cube constituted by six meshes (one plane of the cube corresponds to one mesh) as the object model and a sketch plane represented by points (grid) representing coordinate axes and a grid interval. A user performs design using the sketch plane as a reference plane.
FIG. 14 is a view illustrating an example in which the mesh size and grid interval do not coincide with each other and an example in which the mesh size and grid interval coincide with each other. In particular, in the case where a mesh having the same shape is added, coincidence between the interval of the grid constituting the sketch plane and the length of the side of the mesh allows easy designing. In order to make the grid interval coincide with the length of the mesh side, a user needs to measure the length of the mesh side on the virtual space and manually inputs a result of the measurement in a predetermined grid interval input window.
FIG. 15 illustrates a procedure in which a new mesh is added. A user reads an object model into a virtual space (see “reading of model”) and displays a sketch plane (see “display of sketch plane”). The user inputs, using an input device (e.g., mouse), the length of one side of the object model to which a new mesh is added and executes a command to measure the length of the side. After that, the user manually inputs a result of the measurement in a predetermined grid interval input window to make the grid interval coincide with the side of the mesh (see “adjustment of grid interval”). Thereafter, the user manually inputs a numerical value in a predetermined input dialogue such that coordinate axes coincide with the position and direction to and in which the new mesh is added to thereby move or rotate the sketch plane (see “moving or rotation of sketch plane”). After adjusting the sketch plane as described above, the user uses the input device to instruct addition of the new mesh (see “instruction of addition of mesh”) to complete the addition of the new mesh (see “completion of addition of mesh”).
The details of the mesh will be described here. The mesh is a basic unit of a quadrangle or a triangle forming an object model which is analyzed by an electromagnetic wave analysis software and is defined by four or three points on a three-dimensional world coordinate system (Pw(x,y,z)). Referring to FIG. 16 illustrating an example of an object model constituted by three meshes, a mesh P is defined by four points: P1, P2, P3, and P4, each of which has a value specifying the three-dimensional world coordinate position. Further, the order is defined in each point. For example, P1 is the first, P2 the second, P3 is the third, P4 is the fourth, and P1 comes after P4.
As prior arts relating to the present invention, there are known the following methods: a method that eliminates complication associated with graphic input operation in a graphic display system to improve input efficiency; a method capable of generating three-dimensional shape data of a three-dimensional object in which intention or image of a designer has been reflected; and a method that generates mesh data to be input to a thermo-fluid analysis tool, etc., for an electronic device with ease and high accuracy. Furthermore, there is known an electromagnetic field intensity calculation apparatus with which even beginners can easily create input data at short times so as to effectively perform calculation of an electromagnetic field intensity.    [Patent Document 1] Japanese Laid-open Patent Publication No. 08-16826    [Patent Document 2] Japanese Laid-open Patent Publication No. 2004-206262    [Patent Document 3] Japanese Laid-open Patent Publication No. 2004-94674    [Patent Document 4] Japanese Laid-open Patent Publication No. 11-161690